The University of Pennsylvania Gl Training Program has been instrumental in the development of academic research careers for gastroenterology trainees since 1963. During the last 10 years, there has been tremendous expansion of biomedical research. The Penn Training Program has increased its base of basic science faculty coupled with impressive growth and maturation of the adult and pediatric Gl divisions. Trainees have outstanding opportunities to pursue molecular and cellular biology in the field of gastroenterology. Direction: The Program Director and Associate Directors have an administrative structure that oversees the needs of the Training Program, assisted by an internal Executive Committee and an External Advisory Board. They are complemented by rigorous individual trainee research advisory committees. Faculty: Research faculty from the Adult and Pediatric Gl divisions and basic science departments are selected based upon experience with trainees, independent and externally funded laboratories, and relevant projects in digestive, liver and pancreatic diseases. The faculty are grouped by research interests: 1) Cell growth and differentiation; 2) Immunobiology and host responses; and 3) Developmental biology and genetics. Proposed Training: The cornerstone of the Program is an intensive laboratory-based research experience, which entails close interaction with a training program faculty mentor. This laboratory work is supplemented by an educational curriculum that includes an introductory course in molecular and cellular biology, selected University courses, research seminars and lectures, written and oral research presentations, and seminars on extramural funding and the ethics of scientific research. Candidates: Outstanding trainees with MD or MD-PhD degrees postdoctoral fellows) enter the Program from the Adult and Pediatric Gl Fellowship Programs after being selected through a nationally competitive application process. Additionally, there has been growth in Penn's Physician-Scientist Residency Pathway, and new avenues have emerged to identify future trainees in gastroenterology, including through our NIDDK R25 undergraduate training grant and our medical student training grant supplements.